Developer tools / Diagram maker14 tools

Best diagram makers

Draw flowcharts, architecture and UML diagrams. Facts come from each tool's own pages, and every score says where it comes from. How we rank

Tools: 14
Researched: 5
Free option: 4
Only listed: 9

Disclosure: agathox makes some of the tools listed here. They are labelled and scored by the same method as every other tool.

Ranked by signals we can measure or quote: website health, the facts each tool's own pages state, and community discussion. Nothing here has been hands-on tested yet, so this is not a quality test. How the signals rank works

Quick answer

No signup needed: draw.io

Based on what each tool's own pages say. A tool is left out when its pages say it varies or do not say. Details are listed under each tool.

Show only:

Want two of these head to head? Compare tools side by side.

1
Gliffy
UnclearSignup unclearFile handling unclearHealth 4.8
CompareOpen Gliffy
Details and sources
Free tier
Not stated.
Paid plan
Not stated.
Signup
Users must log into their Atlassian account to evaluate or purchase Gliffy. The page says: “Please log into your account at my.atlassian.com or visit the Atlassian Marketplace to evaluate or purchase Gliffy.”
Watermark
Not stated.
Where files go
Gliffy diagrams are stored as attachments on the Confluence page as .gliffy and .png files. The page says: “Gliffy diagrams are stored as attachments on the Confluence page both as a .gliffy file and an image file (.png).”
From the tool's own pages, checked 2026-11-08. Sources: Pricing. Prices and limits change; check the tool before you rely on them.
Read automatically by a program, not by a person. Each fact quotes the sentence it came from, and a fact is shown only if that sentence is on the page. Where a page did not say, it reads “Not stated.”
Full page for Gliffy
2
Eraser
Free optionSignup unclearFile handling unclearHealth 4.8
CompareOpen Eraser
Details and sources
Free tier
Free plan at $0 per member: 3 files, 3 AI credits, 7-day version history, unlimited guests. Includes AI diagrams, diagram-as-code, real-time collaboration and export to PDF, PNG, SVG and Markdown.
Paid plan
Business: $45 per member per month billed annually, or $60 monthly. Business Plus: $42 per member per month billed annually, minimum 10 seats. Enterprise is custom pricing.
Signup
Not stated.
Watermark
Not stated.
Where files go
Privacy policy says data is processed at the company's offices and other places, and may be transferred outside your country. No specific retention periods. It does not say how diagrams or documents are stored or deleted.
From the tool's own pages, checked 2026-11-01. Sources: Pricing, Privacy policy. Prices and limits change; check the tool before you rely on them.
Full page for Eraser
3
Creately
Free optionSignup unclearFile handling unclearHealth 4.4
CompareOpen Creately
Details and sources
Free tier
Free plan at $0. Infinite canvas, all diagram types, up to 45 shapes per diagram, whiteboard with real-time collaboration, team link sharing. Exports (PNG, JPEG, PDF, SVG) are not included.
Paid plan
Pro (unlimited shapes and diagrams, exports, private links) and Business (adds admin controls, roles, audit log) are listed. Enterprise is custom pricing on an annual agreement. Pro and Business prices are not shown on the page text.
Signup
Not stated.
Watermark
Not stated.
Where files go
Privacy policy says personal data is stored on computers in the region chosen at sign-up and may be processed in the US, EU, Australia or other countries. Data is kept only as long as needed; no specific period. Deletion can be requested by email.
From the tool's own pages, checked 2026-11-01. Sources: Plans, Privacy policy. Prices and limits change; check the tool before you rely on them.
Full page for Creately
4
dbdiagram.io
Free optionSignup unclearFile handling unclearHealth 4.8
CompareOpen dbdiagram.io
Details and sources
Free tier
Free plan: up to 10 diagram and doc projects, 10 ER diagrams, 1 diagram view, 14-day schema changelog history, single editor, unlimited viewers. Includes SQL import/export, PDF/PNG/SVG export and public view-only sharing.
Paid plan
Personal Pro $8/mo (unclear if annual or monthly billing). Team $75/mo with 3 editors, extra editors $5/mo. Custom plan by contact. A monthly/annual toggle says annual saves up to 42%.
Signup
Not stated.
Watermark
Not stated.
Where files go
Not stated.
From the tool's own pages, checked 2026-11-01. Sources: Pricing. Prices and limits change; check the tool before you rely on them.
Full page for dbdiagram.io
5
draw.io
Free optionNo signupFile handling unclearHealth 4
CompareOpen draw.io
Details and sources
Free tier
draw.io is free forever with no sign-up required and no lock-in. The page says: “Free forever • No sign-up required • No lock-in.”
Paid plan
Not stated.
Signup
No account or credit card is required to use draw.io. The page says: “No account required. No credit card. Just open and create.”
Watermark
Not stated.
Where files go
Users can store their data wherever they want, and draw.io cannot access it. The page says: “Store your data wherever you want. We cannot access it—ever.”
From the tool's own pages, checked 2026-11-08. Sources: Home. Prices and limits change; check the tool before you rely on them.
Read automatically by a program, not by a person. Each fact quotes the sentence it came from, and a fact is shown only if that sentence is on the page. Where a page did not say, it reads “Not stated.”
Full page for draw.io

Diagram maker: tools compared
Tool	Free option	Signup	Your files	Scores	Compare, open or show details
1Gliffy	Unclear	Unclear	Unclear	Health 4.8Signals 4.1	CompareOpen
Free tier Not stated. Paid plan Not stated. Signup Users must log into their Atlassian account to evaluate or purchase Gliffy. The page says: “Please log into your account at my.atlassian.com or visit the Atlassian Marketplace to evaluate or purchase Gliffy.” Watermark Not stated. Where files go Gliffy diagrams are stored as attachments on the Confluence page as .gliffy and .png files. The page says: “Gliffy diagrams are stored as attachments on the Confluence page both as a .gliffy file and an image file (.png).” From the tool's own pages, checked 2026-11-08. Sources: Pricing. Prices and limits change; check the tool before you rely on them. Read automatically by a program, not by a person. Each fact quotes the sentence it came from, and a fact is shown only if that sentence is on the page. Where a page did not say, it reads “Not stated.” Full page for Gliffy
2Eraser	Yes	Unclear	Unclear	Health 4.8Signals 3.9	CompareOpen
Free tier Free plan at $0 per member: 3 files, 3 AI credits, 7-day version history, unlimited guests. Includes AI diagrams, diagram-as-code, real-time collaboration and export to PDF, PNG, SVG and Markdown. Paid plan Business: $45 per member per month billed annually, or $60 monthly. Business Plus: $42 per member per month billed annually, minimum 10 seats. Enterprise is custom pricing. Signup Not stated. Watermark Not stated. Where files go Privacy policy says data is processed at the company's offices and other places, and may be transferred outside your country. No specific retention periods. It does not say how diagrams or documents are stored or deleted. From the tool's own pages, checked 2026-11-01. Sources: Pricing, Privacy policy. Prices and limits change; check the tool before you rely on them. Full page for Eraser
3Creately	Yes	Unclear	Unclear	Health 4.4Signals 3.7	CompareOpen
Free tier Free plan at $0. Infinite canvas, all diagram types, up to 45 shapes per diagram, whiteboard with real-time collaboration, team link sharing. Exports (PNG, JPEG, PDF, SVG) are not included. Paid plan Pro (unlimited shapes and diagrams, exports, private links) and Business (adds admin controls, roles, audit log) are listed. Enterprise is custom pricing on an annual agreement. Pro and Business prices are not shown on the page text. Signup Not stated. Watermark Not stated. Where files go Privacy policy says personal data is stored on computers in the region chosen at sign-up and may be processed in the US, EU, Australia or other countries. Data is kept only as long as needed; no specific period. Deletion can be requested by email. From the tool's own pages, checked 2026-11-01. Sources: Plans, Privacy policy. Prices and limits change; check the tool before you rely on them. Full page for Creately
4dbdiagram.io	Yes	Unclear	Unclear	Health 4.8Signals 3.7	CompareOpen
Free tier Free plan: up to 10 diagram and doc projects, 10 ER diagrams, 1 diagram view, 14-day schema changelog history, single editor, unlimited viewers. Includes SQL import/export, PDF/PNG/SVG export and public view-only sharing. Paid plan Personal Pro $8/mo (unclear if annual or monthly billing). Team $75/mo with 3 editors, extra editors $5/mo. Custom plan by contact. A monthly/annual toggle says annual saves up to 42%. Signup Not stated. Watermark Not stated. Where files go Not stated. From the tool's own pages, checked 2026-11-01. Sources: Pricing. Prices and limits change; check the tool before you rely on them. Full page for dbdiagram.io
5draw.io	Yes	Not needed	Unclear	Health 4Signals 3.6	CompareOpen
Free tier draw.io is free forever with no sign-up required and no lock-in. The page says: “Free forever • No sign-up required • No lock-in.” Paid plan Not stated. Signup No account or credit card is required to use draw.io. The page says: “No account required. No credit card. Just open and create.” Watermark Not stated. Where files go Users can store their data wherever they want, and draw.io cannot access it. The page says: “Store your data wherever you want. We cannot access it—ever.” From the tool's own pages, checked 2026-11-08. Sources: Home. Prices and limits change; check the tool before you rely on them. Read automatically by a program, not by a person. Each fact quotes the sentence it came from, and a fact is shown only if that sentence is on the page. Where a page did not say, it reads “Not stated.” Full page for draw.io

Free option, signup and file handling come from each tool's own pages (“Unclear” means they do not say). Hover a score for what it means. Tick “Compare” on two to four tools to read them side by side.

Answers come from each tool's own pages (“Unclear” means they do not say). Tick “Compare” on two to four tools to read them side by side.

Also listed (9, not yet tested)

Each of these answered when we visited its site. We have not tested them or recorded facts, so they are in alphabetical order, not ranked.

D2
D2 is listed for: diagram maker.
Open
Excalidraw
Excalidraw is a virtual collaborative whiteboard tool that lets you easily sketch diagrams that have a hand-drawn feel to them.
Open
Lucidchart
Create next-generation diagrams with AI, data, and automation in Lucidchart. Understand and optimize every system and process.
Open
Mermaid
Mermaid is a JavaScript diagramming and charting tool that renders Markdown-inspired text definitions into flowcharts, sequence diagrams, Gantt charts and more.
Open
PlantUML
Easily create beautiful UML Diagrams from simple textual description. There are also numerous kind of available diagrams. It's also possible to export images in PNG, LaTeX, EPS, SVG.
Open
SmartDraw
SmartDraw is the best way to make diagrams like flowcharts, org charts, floor plans, and more.
Open
Structurizr
Structurizr is listed for: diagram maker.
Open
Visual Paradigm Online
Visual Paradigm Online offers a comprehensive solution to bring all your documents, presentations, PDFs, charts, and digital publications together under one roof.
Open
Whimsical
Design and document implementation with diagrams. Shape UI with wireframes. Collaborate with your team and AI.
Open